Carburetor supplementary fuel feed



Nov.. 24, 11953 Filed May 27, 1949 D. E. ANDERsoN y v2,660,417 Y CARBURETOR SUPPLEMENTARY FUEL FEED DEVICE WITH AUXILMFUEL PUMP Patented Nov. 24, 1953 'CARBURETOR SUPPLEMENTARY FUEL FEED DEVICE WITH AUXILIARY FUEL PUMP David E. Anderson, Cleveland, Ohio,

Thompson Products, Inc.,

corporationof Ohio assignor to Cleveland, Ohio, a

Application May 27, 1949, Serial No. 95,829

2 Claims.

This invention relates to -devices for feeding controlled amounts of coolant or anti-detonant fluid to the fuel intake of an internal combustion engine. Specifically, this invention has to do with an anti-detonant fuel feeding device featuring, in addition to the usual vacuum voperated supplementary feed device, an auxiliary pump which acts only during a condition of very low vacuum to feed an extra, metered quantity of antidetonant fuel to the fuel intake of the engine.

It is known in the art that engine detonation varies with compression ratio, the quality and type of fuel being burned, and the load on the engine. Likewise, the feeding of supplementary fuels, such as water, alcohol, and the like, to internal combustion engines for power output of the engine is known. It is also known that during smooth running periods of the engine the intake manifold vacuum is relatively high. However, when the engine is rapidly accelerated or a load is suddenly put on the engine, the intake manifold pressure will rapidly increase and very low vacuum conditions will exist, whereupon the engine will tend to knock. Upon occurrence of such a low vacuum condition, in order to prevent such knocking, the device of the present invention will quickly act to inject an extra charge of anti-detonant fluid to supplement any antidetonant feed then being added to the engine.

Accordingly, there is provided in this invention an auxiliary feed device including a housing dening an upper vacuum chamber and a lower vacuum chamber in flow communication with each other and with a source of vacuum. A float controlled fluid storage chamber is disposed in the housing between the upper and lower vacuum chambers and is in flow lcommunication with a discharge conduit leading to the fuel intake passage of the engine.

A spring-pressed diaphragm is disposed in the upper vacuum chamber and is arranged, in the usual manner, .to close a control valve in the conduit between the float chamber and the engine fuel intake in response to increasing vacuum in the upper vacuum chamber. A second diaphragm is disposed in the lower vacuum chamber and is arranged to flex against the compression of a spring as the vacuum in this lower chamber is increased.

This second diaphragm divides the lower chamber into a vacuum chamber and a fluid storage compartment which is supplied with fluid from the iioat chamber. A pair of ball-type check valves maintain a predetermined quantity of fluid above the diaphragm in the storage compartment 2 which also has a passageway leading to the fuel inlet of the engine.

Thus, if the engine intake manifold has attained a high vacuum condition running, for example, at half throttle, the high vacuum in the upper vacuum chamber would draw the diaphragm therein downwardly to close the metering valve and prevent the discharge of further supplementary anti-detonant fluid to the engine. In this high vacuum running condition the engine does not need a supplementary anti-knock uid. In the lower vacuum chamber this high vacuum condition will draw the diaphragm into a cocked position against the compression of the spring.

Now, if the engine is suddenly accelerated to full throttle, a low vacuum condition will occur in the engine intake manifold, and the diaphragm in the upper chamber will be actuated by the compressed spring to open the metering valve and permit supplementary anti-knock fluid to be drawn into the engine fuel intake. In the lower vacuum chamber the coiled spring will actuate the diaphragm upwardly to force a predetermined quantity of supplementary antidetonant fluid into the engine.

Thus, there is provided in this invention ,an auxiliary, vacuum-actuated diaphragm effective under suddenlow vacuum conditions to discharge a jet of anti-detonant fluid into the intake passage of the engine to supplement the antidetonant fluid being normally supplied under low vacuum conditions by the usual supplementary fuel feed device.

Accordingly, it is an object of this invention to provide a supplementary fuel feed device arranged to not only supply anti-knock uid to an engine in response to intake manifold conditions, but to inject an additional quantity when sudden low vacuum conditions are encountered.

Another object of this invention is to provide, in an anti-detonant fuel feed device, a supplementary vacuum controlled chamber that, by means of a calibrated spring, may be arranged to supply an additional quantity of fluid only after a predetermined minimum drop in vacuum pressurein the engine manifold.

Other and further features, advantages and objects of the present invention will become apparent to one skilled in the art from the following detailed description taken in connection with the accompanying drawings.

On the drawings:

Figurev 1 is a vertical central sectional view of a fuel feed device constructed according to the teachings of the present invention, shown connected to the carburetor of an engine;

Figure 2 is a central vertical sectional View similar to Figure l but showing the mechanism of this feed device in a different operating po sition;

Figure 3 is va Vtop'plan view of the device of Figure l; and

Figure 4 is a horizontal sectional view taken on line IV-IV of Figure 2.

As shown on the drawings:

In Figure 1 the reference vnumeral l0 designates generally a supplementary feed device constructed according to the teachings Vof .this invention and mounted by means of ange or mounting block Il which is attached to a carburetor i2. The block Il carries passageways I3 and Hi receiving tubular nozzles l5 and l5, respectively, which extend into the Venturi openings of the carburetor. As seen in Figure 3 and in Figure 4, the carburetor l2 is a dual carburetor and therefore two sets of nozzles l5 and I6 are provided on this feed device. As is customary, fuel feed from the carburetor is controlled by a throttle valve I8.

The device I0 includes a main body portion 25 having a recess 2| in the upper ysurface thereof with a cover member 22 suitably secured across said recess. A exible diaphragm 24 is secured at its marginal edges between the body 20 and the cover 22 and extends across the recess 2l defining an upper chamber 25 vented to atmosphere by a vent hole 25 in the cover and a lower vacuum chamber 21 connected by a tting 2S (Figure 3)., a tube 29 and a tting'i (Figure l) to the fuel inlet passage V32 of the engine.

A cup-shaped lower casing portion 33 is held in sealed engagement with the body '20 with a gasket 34 of resilient material therebetween by means of a plurality of cap screws (not shown) The lower surface of the casing portion 33 has` a recess 36 which is enclosed by a closure plate A31 secured to the casing 33 by any suitable means.

n A diaphragm 39 is disposed across the recess 36 having marginal edges secured between the casing 33 and the closure plate v31. The diaphragm, in connection with the casing 33 and the closure plate 31, defines an upper fluid storage compartment 4I and a lower vacuum chamber 42 which is in communication with the upper vacuum chamber 21 by means of a passageway 43 in the closure plate 31, an aperture 45 Yin the diaphragm 39, a passageway .44 in the casing k33, an aperture in the gasket 34 anda passageway 45 in the body 20.

An annular iioat 41 is `pivotally mounted in a central chamber 48 of the cup-shaped casing 33 by means of a pin 49 on a `depending ange 5G secured to the body 20. A tubular valve housing 52 is threaded into an opening 53 in the body 2B having an inner end portion bottomed against the end wall of the opening .53 with a gasket 54 therebetween. The tubular housing 52 has a central chamber 55 with a restricted orice 5E at one end. The orifice 55 is in alignment with a central passage in the gasket 54 and a passage 51 in the body 20 affording communication between the chamber 55 and a tubular passage 59 connected to a source of anti-detonant fuel.

A valve 65 is slidably disposed in the chamber 55 and has a conical seating surface movable into the restricted orifice 56 and coacting with the edges thereof to control flow of fluid through the .housing into the float chamber 48. An arm 4 6I of the iioat 41 acts on the lower end of the valve 5D to move the conical seating surface of the valve into the orifice 56 to stop the fiow of fluid into the chamber 48 when the fluid in the chamber is at the desired level.

A lower boss 53 depending from the body portion 20 extends downwardly into the float chamber 48 and has a central bore or passage 54 in communication with a central passage 55 of substantially larger diameter in an upper boss :E6 of the body 25 which extends upwardly in an upper boss 15S of the body 25 which extends upwardly into the vacuum chamber 21. The

vlower boss 33 terminates in an internally threaded vportion '38 arranged to receive the threaded lower end of a tubular vent member E9 which Ais centrally disposed in the passage 64 and .has a central bore 15. A spacer ring 1i is disposed about the tubular member 69 at the upper end thereof where the passage 65 merges with the larger passage 55 of the upper boss ,65. it will thus be seen that the lower end of the passage 55 forms a discharge chamber for fluid leaving the passage 15. A passage 12 is provided in the body 25 establishing communication between the passage 55 and the passage E3 in the block Il.

An annular shoulder 13 extends downwardly from the spacci' ring 'i l between thetubular member t9 and the outer wall of the central passage 5t in the lower boss 53 providing an annular passage 1li which is in communication with that portion of the float chamber above the shut-pif position of the float by means of a slantedpas- `sage 15. This upper portion of the oat chamber t8 is vented to atmosphere through an opening 16 in the body 2Q.

To establish communication between the annular passage i4 and the central passage 15 of the tubular member S9 there is provided a series of radially extending passages 1B in the tubular member 69. The passageway at the center of the tubular member @il is also in ,communication with the liquid in the float chamber Q8 through a restricted passageway or orifice 1.9 in the threaded end of the tube 69.

Liquid in the float chamber 48 will, of course, pass upwardly through the passageway 'i5 into the central portion of the tubular passage 59 and stand at a height 'therein corresponding to the height of the liquid in the float chamber.

The metering valve of the present invention comprises an elongated central rod 84, a lower pointed metering end portion cooperating with the restricted orifice 19, and an upper end portion ,86 which is secured in the lower end of a cylindrical sliding block 88 which is slidably disposed in the opening 65 in the upper boss 66.

The central portion of the diaphragm 24 is held between washers S9 and 3i) on a shoulder 9i of the block 88 by means of a peened-over end 92. Thus, flexing movement of the diaphragm 24 will cause the cylindrical block EB to slide up and down in the central passage 55 is the boss 66 and movethe pointed valve seating portion toward or away from the edges of the restricted orifice 19.

The block 88 has a conical shaped lower end 88a coacting with the upper edges of the hole in the spacer ring 1l as shown in Figure 2 to act as a shut-off valve, since the pointed end 85 of the rod'tl is merely a metering valve which does not afford a positive shut-off.

The cylindrical block 88 has a central passage 89 in its upper portion which communicates with a radial passage 55 which is in communication abcd-'41d with an annular groove 96 on the outer periphery of the block 88. It will, of course, be recognized that should the peripheral surfaces of the valve block 83 or the surfaces of the upstanding boss 66 become worn so that liquid can pass up between the boss 56 and the block 68, the suction pressure in the chamber 21 caused by the connection of the chamber 2S with the intake manifold of the engine through the tubular member 26 would cause liquid to be drawn up through these slight openings into the vacuum chamber 2. However, since the annular groove 96 is vented to atmosphere through the passage 89 and the vented chamber 25, the eiiect of the vacuum between the surfaces of the body 88 and the boss S6 is broizen at this point. Therefore, the

vacuum will not be effective to draw liquid up past these surfaces.

A pair of concentric coil springs 93 and 84 are disposed in the vacuum chamber 21 between the main body 2t and the lower washer member 89. It is to be noted that the outer spring member 6d extends the entire distance between the washer 8i? which carries the diaphragm L24 and the body 2Q while the inner and heavier spring 93 does not extend all the Way between these surfaces.

Downward movement of the diaphragm 24 and the associated cylindrical block 88 is effected 'by suction pressure in the intake manifold through the tube 2Q which communicates the chamber 2l with the intake manifold 32. The springs 93 and 94 resist the downward movement of the diaphragm and are strong enough to overcome the pull on the diaphragm 24 when there is low vacuum in the intake manifold, thus permitting anti-detonant fluid to be drawn through the restricted orifice 'i9 and the passage |3 into the fuel intake passage of the engine. Under conditions of high vacuum, the springs permit the diaphragm to be progressively pulled down until the conical end 58a of the block 88 is seated on the top edge of the hole in the spacer ring 1|, thus shutting off the supply of anti-detonant fluid. Prior to a full seating of the end 68a, however, the metering valve 65 will progressively diminish the flow.

The lower diaphragm 3S which is disposed between the iiuid storage chamber 4| and the lower vacuum chamber l2 is arranged to flex against the compression of a spring 91 when the vacuum in the chamber 42 is increased. The diaphragm has a central portion comprising two oppositely disposed washer members 98 and 39 and a depending stop member l which is arranged to abut the cover 3l and limit the downward movement of the diaphragm.

As the diaphragm 39 is flexed against the action of the spring, uid enters the storage chamber #il through a ball check valve assembly including a cap member |02 with a restricted orifice |93, a ball member |04 and a stop pin |05 which restricts the movement of the ball |64 away from the orifice E533. When the ball moves away from the orifice m3 fluid will flow into the storage chamber 4|. A passage |66 in the body portion 33 communicates the storage chamber 4| with a passage |91 which is in communication with the passageway hi in the iiange portion Il and a passageway m3 in the body 20. A ball check valve assembly is disposed between the passages |535 and |01 and comprises a sleeve valve body E39 having an orifice ||0 at one end thereof and a limit bar disposed across the central passageway of the valve body. A ball member H12 is arranged in the passage to move between the port H0 and the stop to permit 6 iiuid to flow from the storage chamber 4| to'v the nozzle I6 and then into the intake of the engine.

In operation, when the engine attains a high vacuum running condition the diaphragm 39 will be flexed against the compression of the spring 91 and fluid will be stored in the chamber above the diaphragm. This condition is indicated in Figure 2 where the throttle valve i8 is partly open. Then, when a sudden low vacuum condition arises in the intake manifold, as, for example, when the valve it is suddenly moved to the Wide open position of Figure l, the spring will suddenly overcome the vacuum pressure in the chamber 42 and flex the diaphragm to compress the uid in-the storage chamber 4| and propel a iet of fluid through the passages |96, |07, |18 and I4 and through the nozzle le into the carburetor. 1 vFrom the foregoing description it is seen that there is provided in this invention a supplementary fuel feed device including a ilexible diaphragm which is moved to a spring-loaded position by a high vacuum running condition of the engine and which is released for ejecting a predetermined quantity of fluid into the fuel intake of the engine in response to a sudden low vacuum condition of the engine. By employing springs 91 of varying load characteristics the pressure at which this supplementary jet of fuel is injected into the carburetor can be regulated. Further, by using a variable stop device IUE, the amount of liquid which would be drawn into the supply chamber 4| can be controlled as well as the length of the stroke of the diaphragm in response to the action of the spring. Thus, there is provided in this invention means for regulating the quantity of fuel injected by this supplementary fuel feed device and the pressure conditions at which it will be injected.

It will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention, and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. A device for feeding fluid to the fuel intake of a combustion engine comprising a housing defining a iioat chamber and having upper and lower substantially central bosses, aligned top and bottom bores extending through said bosses, a restricted orice in said bottom bore, said top bore providing a discharge chamber at the upper end of said bottom bore, said housing having a discharge passageway in communication at one end with the fuel intake of the engine and the other end in communication with said discharge chamber, said housing having a irst diaphragmcovered vacuum chamber subjected to engine manifold vacuum, a block connected to said first diaphragm and slidable in said top bore, said block having an end seatable against the top of said bottom bore to close the bore and an extension coacting with said orifice for metering flow to said end, spring means tending to move said block for increasing the area of said orice, said spring means being disposed in said vacuum chamber and effective during initial movement of said diaphragm to provide a spring rate for increasing'ow of fluid to the discharge passage,

a second vacuum chamber subjected to engine manifold vacuum through said first vacuum chambenla diaphragm disposed in said second chamber, a spring in said second chamber re- 7 sisting the :movement `of :said diaphragm :as the vacuumincreases in said second chamber, acompartment in said Yhousing above .said second chamber in ow communication with -said oat chamber and withthe intake iof ksaid engine, onewayow valve meansbetween said Vfloat chamber and saidcompartment for filling of'saidcompartment during flexing movement of said diaphragm against the action of said spring in response Ato an .increase of vacuum and for preventing discharge from said compartment to said float chamber, andadditional valve means for accommodation of discharge of Viiuid from said com- `partment to the Yengineintake when a decrease in manifoldpressure accommodates flexing of the diaphragm `under .the 4influenceof the compressed spring.

2. A supplementary fuel feed device for acarburetor including a side mounting block :having passages 'extending to the carburetor Venturi, comprising: a housing arranged for attachment to -the side mounting block and having a main fuel chamber; a rst diaphragm secured against the `upper end of said housing and defining therewith a. first vacuum chamber arrangedfor connection to engine intake Vacuum; a second diaphragm secured against the lower end of 'said housing and defining therewith a fuel storage chamber; a cup secured against the lower end of said housing under said second diaphragm and defining therewith -a second vacuum chamber; compression spring means 4between said cupand said second diaphragm; said housing having a rst passage establishing communication between saidtiirstfandA-second .vacuumchambers-a second passage arranged for one-Way ow from said main fuelchamber tosaidfuel storage chamber, a third passage arranged `for one-way iiow from said fuel storagechamber through one of the mounting block passages to the carburetor venturi, a fvertical bore between said rst vacuum chamber and said :main fuel chamber, and a fourthpassage arranged for fuelliow from an intermediate point on said bore through another of the mounting block 'passages to the carburetor venturi; a block 'affixed to said first diaphragm and slidable in the upper end of said vertical bore and `arranged to lprevent fuel ilow through said fourth passage `with high Aengine .intake vacuums, restrictedrpassage means 'at the lower extremity of'said bore; and a rod aiiixed to said block and having a lower tapered end cooperating with said restricted passage means to meter fuel iiow through said fourth passage in accordance with engine intake vacuum.

DAVID E. ANDERSON.

References Cited inthe file of this patent UNITED STATES PATENTS Number Name Date '2,328,604 Bicknell Sept. 7, 1943 2,337,982 Ericson Dec. 28, 1943 2,389,922 Mennesson Nov. 27, 1945 2,394,663 Carlson et al.. Feb. 12, 1945 2,441,301 Waag et al May l1, 1948 2,529,655 Henning Nov. 14, 1950 2,551,719 Ball May 8, 1951 

